Application of thiazole thioketone compound in chemical copper plating and chemical copper plating solution

Abstract

The invention discloses an application of a thiazole thioketone compound in chemical copper plating and a chemical copper plating solution, and belongs to the technical field of chemical plating. The thiazole thioketone compound with the structure shown in the formula I and the nitrogen-containing heterocyclic compound are combined to be used for chemical copper plating, the deposition speed of the chemical copper plating solution can be increased, the chemical copper plating solution has excellent stability, meanwhile, the electroplating hole filling effect after chemical copper plating can be improved, and correspondingly, the prepared chemical copper plating solution has good bath solution stability, and the chemical copper plating solution can be applied to chemical copper plating. When the copper plating solution is applied to a chemical copper plating method, the deposition rate of chemical copper plating and the compactness of a plating layer can be effectively improved. # imgabs0 #

Description

Technical Field

[0001] The present application relates to the technical field of chemical plating, and in particular to the application of thiazolethione compounds in chemical copper plating and a chemical copper plating solution. Background Art

[0002] The electroless copper plating process is widely used to deposit copper on various types of materials. For example, in the manufacture of printed circuit boards, electroless copper plating can be used to deposit electroless copper on the walls of through-holes, blind vias and inner circuit channels as a seed layer for subsequent electroplating of copper.

[0003] However, the additives used in the traditional method to improve the plating speed and stability of the chemical copper plating solution have a greater impact on electroplating hole filling, which may cause problems such as severe blind hole depression. However, additives are indispensable. Removing a small amount of additives may greatly reduce the plating speed and stability of the chemical copper plating solution, resulting in insufficient copper deposition thickness and easy precipitation of copper ions in the bath solution. Summary of the invention

[0004] Based on this, it is necessary to provide an application of thiazolethione compounds in chemical copper plating and a chemical copper plating solution. The thiazolethione compounds and nitrogen-containing heterocyclic compounds are used in combination for chemical copper plating, which can increase the deposition rate of the chemical plating solution and have excellent stability, and can also improve the electroplating hole filling effect after chemical copper plating.

[0005] In a first aspect of the present application, a thiazolethione compound is used in chemical copper plating, wherein the thiazolethione compound is used in combination with a nitrogen-containing heterocyclic compound;

[0006] The thiazolethione compound has a structure shown in Formula I:

[0007] Formula I;

[0008] Wherein, R1 is selected from the following free group: hydrogen, C1-C10 carboxyl, substituted or unsubstituted amine, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted silicon and -CO-R4; R4 is selected from C1-C5 alkoxy or C1-C5 alkyl;

[0009] R2 is selected from the following free group: hydrogen, C1-C10 carboxyl and C1-C10 alkyl;

[0010] R3 is selected from the following free group: hydrogen, =O and =CH-R5; R5 is selected from H or C1-C5 alkoxy;

[0011] When R1 is selected from substituted amine, substituted C1-C10 alkyl or substituted C2-C10 alkenyl, the substituents are each independently selected from C2-C5 alkanoyl or C1-C5 alkoxy; when R1 is selected from substituted silicon, the substituent is C1-C5 alkyl.

[0012] In some embodiments, the nitrogen-containing heterocyclic compound includes at least one of benzotriazole, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole and mercaptobenzotriazole.

[0013] In some embodiments, when R1 is selected from substituted amine, the substituent is C2-C5 alkanoyl;

[0014] When R1 is selected from substituted C2-C10 alkenyl, the substituent is C1-C5 alkoxy.

[0015] In some embodiments, R1 is selected from the following free group: hydrogen, C1-C2 carboxyl, substituted or unsubstituted amine, C1-C4 alkyl, substituted or unsubstituted C2-C3 alkenyl, substituted or unsubstituted silicon and -CO-R4; R4 is selected from C1-C2 alkoxy or C1-C2 alkyl;

[0016] R2 is selected from the following free group: hydrogen, C1-C2 carboxyl and C1-C4 alkyl;

[0017] R3 is selected from the following free group: hydrogen, =0 and =CH-R5; R5 is selected from C1-C2 alkoxy.

[0018] In some embodiments, the thiazolethione compound includes at least one of the following: the thiazolethione compound includes at least one of the following: thiazolidine-2-thione, 3-methylthiazolidine-2-thione, 2-mercapto-4-methyl-2-thiazoline, 3-isopropylthiazolidine-2-thione, 3-isobutyl-2-thiazolidinethione, 3-butyl-2-thiazolidinethione, 1-(2-thioxo-3-thiazoline)ethanone, 2-mercapto-5-thiazolidinone, 2-thioxothiazolidine-4-carboxylic acid, 1-(2-thione-3-thiazolidinyl)-1-propanone, 3-(trimethylsilyl)-2-thiazolidinethione and 2-thione-3-thiazolidinecarboxylic acid ethyl ester.

[0019] In some embodiments, the mass ratio of the thiazolethione compound to the nitrogen-containing heterocyclic compound is 1:(0.2-5).

[0020] The second aspect of the present application provides a chemical copper plating solution, comprising an additive; the additive is a combination of a thiazolethione compound having a structure as shown in Formula I and a nitrogen-containing heterocyclic compound.

[0021] In some embodiments, the chemical copper plating solution further comprises a copper ion source, a complexing agent, a reducing agent, a pH adjusting agent, a stabilizer and a solvent.

[0022] In some embodiments, the copper ion source includes at least one of copper sulfate, copper chloride, copper nitrate, copper hydroxide, and copper acetate;

[0023] and / or the complexing agent comprises at least one of potassium sodium tartrate, sodium tartrate, dipotassium tartrate, ethylenediaminetetraacetic acid, disodium ethylenediaminetetraacetate, N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine, sodium salicylate, citrate, triethanolamine, iminodiacetic acid, nitrilotriacetic acid, D-mannitol, xylitol and D-sorbitol;

[0024] and / or the reducing agent comprises at least one of formaldehyde, hypophosphite, glyoxylic acid, dimethylaminoborane, borohydride salts, ascorbic acid, iron or cobalt complexes, sodium hydroxymethanesulfinate and thiourea dioxide;

[0025] and / or the pH adjuster includes at least one of sodium hydroxide, potassium hydroxide, sodium carbonate, ammonia water, nitric acid, sulfuric acid, and hydrochloric acid;

[0026] And / or the stabilizer includes at least one of 2,2'-bipyridine, 4,4'-bipyridine, phenanthroline and derivatives, thiols, thiothreitol, thioethers, 2,2-thiodiethanol, thiourea and derivatives, cyanide, NaCN, KCN, nickel potassium cyanide, ferrocyanide, K4[Fe(CN)6], thiocyanate, selenocyanate, iodide, sulfite, thiosulfate, polyethylene glycol and polypropylene glycol.

[0027] In some embodiments, in the chemical copper plating solution, the concentration of the additive is 0.1 mg / L-60.0 mg / L, the concentration of the copper ion source is 0.3 g / L-30.0 g / L, the concentration of the complexing agent is 10 g / L-170 g / L, the concentration of the reducing agent is 0.5 g / L to 80.0 g / L, and the concentration of the stabilizer is 0.1 mg / L-50.0 mg / L; the pH of the chemical copper plating solution is ≥8.5.

[0028] The third aspect of the present application provides a chemical copper plating method, which uses the above-mentioned chemical copper plating solution to perform chemical copper plating on a copper-plated part.

[0029] Beneficial effects of this application:

[0030] 1. The present application provides the application of thiazolethione compounds in chemical copper plating. The combination of the thiazolethione compounds and nitrogen-containing heterocyclic compounds can increase the deposition rate of the chemical plating solution and has excellent stability, and can also improve the electroplating hole filling effect after chemical copper plating.

[0031] 2. The present application provides a chemical copper plating solution. When the chemical copper plating solution is used to perform chemical copper plating on a workpiece to be copper-plated, the deposition rate of the chemical copper plating can be effectively increased, the electroplating hole filling ability can be improved, and the chemical copper plating solution also has good tank liquid stability.

[0032] 3. The present application also provides a chemical copper plating method. The use of the chemical copper plating solution can effectively improve the deposition rate of the chemical copper plating and the density of the coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art description. The drawings are only used to illustrate the preferred implementation methods and are not considered to be limitations of the present application. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0034] Figure 1 This is a metallographic photograph of the blind hole test board after copper plating in Example 1.

[0035] Figure 2 This is a metallographic photograph of the blind hole test board after copper plating in Example 4.

[0036] Figure 3 This is a metallographic photograph of the blind hole test board after copper plating in Comparative Example 1.

[0037] Figure 4 This is a metallographic photograph of the blind hole test board after copper plating in Comparative Example 2.

[0038] Figure 5 This is a metallographic photograph of the blind hole test board after copper plating in Example 5.

[0039] Figure 6 This is a metallographic photograph of the blind hole test board after copper plating in Comparative Example 3.

[0040] Figure 7 This is a metallographic photograph of the blind hole test board after copper plating of Comparative Example 4. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of this application clearer and to provide a more thorough and comprehensive understanding of the disclosed content of this application, the technical solution of this application will be clearly and completely described below in conjunction with the specific embodiments of this application and the corresponding drawings. The described embodiments are only part of the embodiments of this application, not all of them.

[0042] The implementation of the present application is described in detail below in conjunction with the accompanying drawings. This embodiment is implemented based on the technical solution of the present application, and a detailed implementation method and specific operation process are given, but the protection scope of the present application is not limited to the following embodiments.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0044] the term

[0045] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0046] In the present application, "plurality", "multiple" and the like, unless otherwise specified, refer to a number greater than or equal to 2. For example, "one or more" or "at least one" means one or greater than or equal to two.

[0047] In the present application, the terms "further", "particularly" and the like are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of the present application.

[0048] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0049] In the present application, when it comes to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values ​​in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e., the minimum value and the maximum value) of the numerical interval, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to the integers in the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints, which is equivalent to directly listing each integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be combined. In other words, unless otherwise specified, the numerical range disclosed herein should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. "Numerical interval" allows broadly including numerical interval types such as percentage intervals, ratio intervals, and ratio intervals.

[0050] In this application, unless otherwise specified, the temperature parameter is allowed to be either a constant temperature treatment or to vary within a certain temperature range. It should be understood that the constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuations within the range of ±5°C, ±4°C, ±3°C, ±2°C and ±1°C are allowed.

[0051] In this application, when referring to the unit of a data range, if there is a unit only after the right endpoint, it means that the units of the left and right endpoints are the same. For example, 2-5h means that the units of the left endpoint "2" and the right endpoint "5" are both h (hours).

[0052] In the present application, in expressions about the number of carbons, i.e., the number following the capital letter "C", such as "C1-C10", "C1-C4", etc., the number following "C", such as "1", "4", or "10", indicates the number of carbons in a particular functional group. That is, the functional group may include 1-10 carbon atoms and 1-4 carbon atoms, respectively. For example, "C1-C10 alkyl" refers to an alkyl group having 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 carbon atoms. Suitable examples include, but are not limited to, methyl (Me, -CH3), ethyl (Et, -CH2CH3), 1-propyl (n-Pr, n-propyl, -CH2CH2CH3), 2-propyl (i-Pr, i-propyl, -CH(CH3)2), 1-butyl (n-Bu, n-butyl, -CH2CH2CH2CH3), 2-methyl-1-propyl (i-Bu, i-butyl, -CH2CH(CH3)2), 2-butyl (s-Bu, s-butyl, -C H(CH3)CH2CH3), 2-methyl-2-propyl (t-Bu, t-butyl, -C(CH3)3), 1-pentyl (n-pentyl, -CH2CH2CH2CH2CH3), 2-pentyl (-CH(CH3)CH2CH2CH3), 3-pentyl (-CH(CH2CH3)2), 2-methyl-2-butyl (-C(CH3)2CH2CH3), 3-methyl-2-butyl (-CH(CH3)CH(CH3)2), 3-methyl -1-butyl (-CH2CH2CH(CH3)2) and 2-methyl-1-butyl (-CH2CH(CH3)CH2CH3), 1-hexyl (-CH2CH2CH2CH2CH2CH3), 2-hexyl (-CH(CH3)CH2CH2CH2CH3), 3-hexyl (-CH(CH2CH3)(CH2CH2CH3)), 2-methyl-2-pentyl (-C(CH3)2CH2CH2CH3), 3-methyl-2-pentyl ( -CH(CH3)CH(CH3)CH2CH3), 4-methyl-2-pentyl (-CH(CH3)CH2CH(CH3)2), 3-methyl-3-pentyl (-C(CH3)(CH2CH3)2), 2-methyl-3-pentyl (-CH(CH2CH3)CH(CH3)2), 2,3-dimethyl-2-butyl (-C(CH3)2CH(CH3)2), 3,3-dimethyl-2-butyl (-CH(CH3)C(CH3)3.

[0053] In the present application, "C1-C10 alkyl" is expected to be a straight chain saturated hydrocarbon structure with 1-10 carbon atoms or a branched or cyclic hydrocarbon structure with 3-10 carbon atoms. When specifying an alkyl with a specific carbon number, it is expected to cover all geometric isomers with this carbon number. Therefore, for example, "butyl" means to include normal-butyl, sec-butyl, isobutyl, tert-butyl and cyclobutyl. "propyl" means to include normal-propyl, isopropyl and cyclopropyl. C1-C10 alkyl includes, but is not limited to methyl, ethyl, normal-propyl, isopropyl, cyclopropyl, normal-butyl, isobutyl, sec-butyl, tert-butyl, cyclobutyl, normal-pentyl, isopentyl, neopentyl, cyclopentyl, methylcyclopentyl, ethylcyclopentyl, normal-hexyl, isohexyl, cyclohexyl, normal-heptyl, octyl, nonyl, decyl, cyclopropyl, cyclobutyl, norbornyl etc. In addition, alkyl can be optionally substituted.

[0054] In a first aspect of the present application, a thiazolethione compound is used in chemical copper plating, wherein the thiazolethione compound is used in combination with a nitrogen-containing heterocyclic compound;

[0055] The thiazolethione compound has a structure shown in Formula I:

[0056] Formula I;

[0057] Wherein, R1 is selected from the following free group: hydrogen, C1-C10 carboxyl, substituted or unsubstituted amine, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted silicon and -CO-R4; R4 is selected from C1-C5 alkoxy or C1-C5 alkyl;

[0058] R2 is selected from the following free group: hydrogen, C1-C10 carboxyl and C1-C10 alkyl;

[0059] R3 is selected from the following free group: hydrogen, =O and =CH-R5; R5 is selected from H or C1-C5 alkoxy;

[0060] When R1 is selected from substituted amine, substituted C1-C10 alkyl or substituted C2-C10 alkenyl, the substituents are each independently selected from C2-C5 alkanoyl or C1-C5 alkoxy; when R1 is selected from substituted silicon, the substituent is C1-C5 alkyl.

[0061] It is understandable that the thiazolethione compound may be one of the compounds shown in the above formula I, or a combination of multiple compounds, such as thiazolidine-2-thione, thiazolidine-2-thione and 3-methylthiazolidine-2-thione.

[0062] The thiazolethione compounds shown in formula I are used for chemical copper plating, especially the combination of thiazolethione compounds and nitrogen-containing heterocyclic compounds, which can increase the deposition rate of the chemical plating solution and have excellent stability, and can also improve the electroplating hole filling effect after chemical copper plating.

[0063] In a specific example, the C1-C10 carboxyl group is a carboxyl group containing 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms, including but not limited to -COOH, -CH2-COOH, -(CH2)2-COOH, -(CH2)3-COOH, -(CH2)4-COOH, -(CH2)5-COOH, -(CH2)6-COOH, -(CH2)7-COOH, -(CH2)8-COOH, -(CH2)9-COOH, -CH(CH3)-COOH, -CH(CH3)-CH2-COOH, and the like.

[0064] In a specific example, the C1-C10 alkyl group is an alkyl group containing 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms, including but not limited to methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclobutyl, n-pentyl, isopentyl, neopentyl, cyclopentyl, methylcyclopentyl, ethylcyclopentyl, n-hexyl, isohexyl, cyclohexyl, n-heptyl, octyl, nonyl, decyl, cyclopropyl, cyclobutyl, and norbornyl.

[0065] In a specific example, the C2-C10 alkenyl group is an alkenyl group containing 2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms, including but not limited to ethenyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, isopentenyl.

[0066] In a specific example, the substituents in the substituted amine, substituted C1-C10 alkyl or substituted C2-C10 alkenyl include C2-C5 alkanoyl (alkanoyl of 2, 3, 4 or 5 carbon atoms) and C1-C5 alkoxy (alkoxy of 1, 2, 3, 4 or 5 carbon atoms), including but not limited to formyl, acetyl, propionyl, butyryl, methoxy, ethoxy, propoxy, butoxy, and pentoxy.

[0067] In a specific example, the substituent of the substituted silicon group is an alkyl group of 1, 2, 3, 4 or 5 carbon atoms, including but not limited to methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclobutyl, n-pentyl.

[0068] In a specific example, in -CO-R4, R4 is selected from an alkoxy group of 1, 2, 3, 4 or 5 carbon atoms or an alkyl group of 1, 2, 3, 4 or 5 carbon atoms, and the alkoxy group includes but is not limited to methoxy, ethoxy, propoxy, butoxy, and pentyloxy; the alkyl group includes but is not limited to methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclobutyl, and n-pentyl.

[0069] In a specific example, in =C-R5, R5 is selected from H or an alkoxy group of 1, 2, 3, 4 or 5 carbon atoms, including but not limited to H, methoxy, ethoxy, propoxy, butoxy, pentoxy.

[0070] In some embodiments, the nitrogen-containing heterocyclic compound includes at least one of benzotriazole, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole and mercaptobenzotriazole.

[0071] In some embodiments, when R1 is selected from substituted amine, the substituent is C2-C5 alkanoyl;

[0072] When R1 is selected from substituted C2-C10 alkenyl, the substituent is C1-C5 alkoxy.

[0073] In some embodiments, R1 is selected from the following free group: hydrogen, C1-C2 carboxyl, substituted or unsubstituted amine, C1-C4 alkyl, substituted or unsubstituted C2-C3 alkenyl, substituted or unsubstituted silicon and -CO-R4; R4 is selected from C1-C2 alkoxy or C1-C2 alkyl;

[0074] R2 is selected from the following free group: hydrogen, C1-C2 carboxyl and C1-C4 alkyl;

[0075] R3 is selected from the following free group: hydrogen, =0 and =CH-R5; R5 is selected from C1-C2 alkoxy.

[0076] In some embodiments, R1 is selected from the following free group: hydrogen, -COOH, -CH2-COOH, methyl, ethyl, isopropyl, isobutyl, butyl, allyl, amino, -NH-CO-CH3, -CO-CH2CH3, -CO-O-CH2CH3 and -Si(CH3)3;

[0077] R2 is selected from the following free group: hydrogen, -COOH, methyl and isopropyl;

[0078] R3 is selected from the following free group: hydrogen, =0 and =CH-O-CH2-CH3.

[0079] In some embodiments, the thiazolethione compound includes at least one of the following: the thiazolethione compound includes at least one of the following: thiazolidine-2-thione, 3-methylthiazolidine-2-thione, 2-mercapto-4-methyl-2-thiazoline, 3-isopropylthiazolidine-2-thione, 3-isobutyl-2-thiazolidinethione, 3-butyl-2-thiazolidinethione, 1-(2-thioxo-3-thiazoline)ethanone, 2-mercapto-5-thiazolidinone, 2-thioxothiazolidine-4-carboxylic acid, 1-(2-thione-3-thiazolidinyl)-1-propanone, 3-(trimethylsilyl)-2-thiazolidinethione and 2-thione-3-thiazolidinecarboxylic acid ethyl ester.

[0080] In some embodiments, the mass ratio of the thiazolethione compound to the nitrogen-containing heterocyclic compound is 1:(0.2-5), specifically 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, etc.

[0081] The second aspect of the present application provides a chemical copper plating solution, comprising an additive; the additive is a combination of a thiazolethione compound having a structure as shown in Formula I and a nitrogen-containing heterocyclic compound.

[0082] The combination of the thiazolethione compound and the nitrogen-containing heterocyclic compound of the structure shown in Formula I is used in a chemical copper plating solution. When the chemical copper plating solution is used to perform chemical copper plating on a workpiece to be plated with copper, the deposition rate of the chemical copper plating can be effectively increased, the electroplating hole filling ability can be improved, and the chemical copper plating solution composition also has good tank solution stability.

[0083] In some embodiments, the chemical copper plating solution further comprises a copper ion source, a complexing agent, a reducing agent, a pH adjusting agent, a stabilizer and a solvent.

[0084] In some embodiments, the copper ion source includes at least one of copper sulfate, copper chloride, copper nitrate, copper hydroxide, and copper acetate;

[0085] and / or the complexing agent comprises at least one of potassium sodium tartrate, sodium tartrate, dipotassium tartrate, ethylenediaminetetraacetic acid, disodium ethylenediaminetetraacetate, N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine, sodium salicylate, citrate, triethanolamine, iminodiacetic acid, nitrilotriacetic acid, D-mannitol, xylitol and D-sorbitol;

[0086] and / or the reducing agent comprises at least one of formaldehyde, hypophosphite, glyoxylic acid, dimethylaminoborane, borohydride salts, ascorbic acid, iron or cobalt complexes, sodium hydroxymethanesulfinate and thiourea dioxide;

[0087] and / or the pH adjuster includes at least one of sodium hydroxide, potassium hydroxide, sodium carbonate, ammonia water, nitric acid, sulfuric acid, and hydrochloric acid;

[0088] And / or the stabilizer includes at least one of 2,2'-bipyridine, 4,4'-bipyridine, phenanthroline and derivatives, thiols, thiothreitol, thioethers, 2,2-thiodiethanol, thiourea and derivatives, cyanide, NaCN, KCN, nickel potassium cyanide, ferrocyanide, K4[Fe(CN)6], thiocyanate, selenocyanate, iodide, sulfite, thiosulfate, polyethylene glycol and polypropylene glycol.

[0089] Optionally, the solvent includes water, specifically, at least one of pure water, ultrapure water and deionized water.

[0090] In some embodiments, in the chemical copper plating solution, the concentration of the additive is 0.1 mg / L-60.0 mg / L, the concentration of the copper ion source is 0.3 g / L-30.0 g / L, the concentration of the complexing agent is 10 g / L-170 g / L, the concentration of the reducing agent is 0.5 g / L to 80.0 g / L, and the concentration of the stabilizer is 0.1 mg / L-50.0 mg / L; the pH of the chemical copper plating solution is ≥8.5.

[0091] Optionally, the concentration of the additive may be 0.5 mg / L-45.0 mg / L, further may be 2.0 mg / L-20.0 mg / L, further may be 2.0 mg / L to 10.0 mg / L, specifically, the concentration of the additive may be 0.1 mg / L, 0.5 mg / L, 1.0 mg / L, 2.0 mg / L, 3.0 mg / L, 4.0 mg / L, 5.0 mg / L, 6.0 mg / L, 7.0 mg / L, 8.0 mg / L, 9. 0mg / L, 10.0mg / L, 11.0mg / L, 12.0mg / L, 13.0mg / L, 14.0mg / L, 15.0mg / L, 16.0mg / L, 17.0mg / L, 18.0mg / L, 1 9.0mg / L, 20.0mg / L, 25.0mg / L, 30.0mg / L, 35.0mg / L, 40.0mg / L, 45.0mg / L, 50.0mg / L, 55.0mg / L, 60.0mg / L.

[0092] Optionally, the concentration of the copper ion source can be 0.5g / L-25.0g / L, and further can be 0.5g / L-10.0g / L. Specifically, the concentration of the copper ion source can be 0.5g / L, 1g / L, 2g / L, 3g / L, 4g / L, 5g / L, 6g / L, 7g / L, 8g / L, 9g / L, 10g / L, 15g / L, 20g / L, 25.0g / L, 30g / L, etc.

[0093] Optionally, the concentration of the complexing agent can be 20g / L-140g / L, and further can be 30g / L-65g / L. Specifically, the concentration of the complexing agent can be 10g / L, 20g / L, 30g / L, 35g / L, 40g / L, 45g / L, 50g / L, 55g / L, 60g / L, 65g / L, 75g / L, 85g / L, 95g / L, 100g / L, 110g / L, 120g / L, 130g / L, 140g / L, 150g / L, 160g / L, or 170g / L.

[0094] Optionally, the concentration of the reducing agent can be 0.5g / L-50.0g / L, and further can be 1.0g / L-10.0g / L. Specifically, the concentration of the reducing agent can be 0.5g / L, 1g / L, 1.5g / L, 2g / L, 2.5g / L, 3g / L, 3.5g / L, 4g / L, 4.5g / L, 5g / L, 5.5g / L, 6g / L, 6.5g / L, 7g / L, 7.5g / L, 8g / L, 8.5g / L, 9g / L, 9.5g / L, 10g / L, 20g / L, 30g / L, 40g / L, 50g / L, 60g / L, 70g / L, 80g / L.

[0095] Optionally, the concentration of the stabilizer can be 1.0 mg / L-30.0 mg / L, and further can be 1.0 mg / L-10.0 mg / L. Specifically, the concentration of the stabilizer can be 0.1 mg / L, 1 mg / L, 2 mg / L, 3 mg / L, 4 mg / L, 5 mg / L, 6 mg / L, 7 mg / L, 8 mg / L, 9 mg / L, 10 mg / L, 15 mg / L, 20 mg / L, 25 mg / L, 30 mg / L, 40 mg / L, 50 mg / L.

[0096] Optionally, the pH value of the chemical copper plating solution may be ≥9.0, further may be 9.5-14, further may be 11-13. Specifically, the pH value of the chemical copper plating solution may be 8.5, 9.0, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, or 14.

[0097] The third aspect of the present application provides a chemical copper plating method, which uses the above-mentioned chemical copper plating solution to perform chemical copper plating on a copper-plated part.

[0098] The chemical copper plating method of the present application adopts the above-mentioned chemical copper plating solution, which can effectively improve the deposition rate of chemical copper plating and the density of the plating layer.

[0099] Unless otherwise specified, the raw materials used in the following experiments can be purchased from the market.

[0100] The following are specific embodiments.

[0101] Examples 1-9 and Comparative Examples 1-4

[0102] The formula of chemical copper plating solution is shown in Table 1-2:

[0103] Table 1 Composition of chemical copper plating solution of Examples 1-4 and Comparative Examples 1-2

[0104]

[0105] Table 2 Composition of chemical copper plating solution of Examples 5-9 and Comparative Examples 3-4

[0106]

[0107] Preparation process: Take each component and mix them separately to obtain the chemical copper plating solution of Examples 1-9 and Comparative Examples 1-4.

[0108] Application Example 1

[0109] The PCB board that has completed laser drilling is subjected to chemical copper plating according to the following process: degreasing → micro-etching → pre-immersion → activation → reduction → chemical copper plating. The specific conditions are shown in Table 3:

[0110] Table 3 Process conditions

[0111]

[0112] Among them, TS-ECuSet CL degreaser, TS-ECuSet CL-A degreaser, TS-ECuSet PA prepreg, TS-ECuSet A-1 activator, and TS-ECuSet B reducing agent are all products produced by Guangdong Dongshuo Technology Co., Ltd. and used in the market.

[0113] After the chemical copper plating is completed, the thickness of the chemical copper plating layer is measured, and the deposition rate of the chemical copper plating is calculated as follows:

[0114] The copper coating thickness was determined by X-ray fluorescence (XRF) using an XRF instrument, Fischerscope X-RAY XDV-μ coating thickness gauge (Helmut Fischer GmbH, Germany). After measuring the coating thickness, the obtained layer thickness was divided by the time required for chemical copper plating, 5 min, to obtain the deposition rate of chemical copper plating. The results are shown in Table 4.

[0115] Application Example 2

[0116] Blind hole depression test

[0117] The blind hole test board was treated according to the process flow: degreasing → micro-etching → pre-immersion → activation → reduction → chemical copper plating (see Application Example 1 for details), and then the hole filling electroplating was performed. The obtained samples were vertically sliced ​​and the concavity of the blind hole slices after the hole filling electroplating was observed using a metallographic microscope. The results are shown in Table 4 and Figure 1-7 .

[0118] Table 4 Summary of the performance of Examples 1-9 and Comparative Examples 1-4

[0119]

[0120] As can be seen from Table 4, Examples 1-4 use the defined thiazolethione compounds and nitrogen-containing heterocyclic compounds in combination for chemical copper plating solution, which can effectively improve the deposition rate of chemical copper plating, and can improve the hole filling depression after chemical copper plating, and the chemical copper plating solution also has better stability. Comparative Example 3 uses only 3-methyl-2-thione-1,3-thiazoline-4-one, and Comparative Example 4 uses 3-methyl-2-thione-1,3-thiazoline-4-one as a thiazolethione compound and a nitrogen-containing heterocyclic compound to prepare a chemical copper plating solution, and its deposition rate is significantly deteriorated, and the blind hole depression is obvious. It can be seen that only the combination of the thiazolethione compounds and nitrogen-containing heterocyclic compounds defined in this application has an ideal technical effect.

[0121] In addition, Examples 5-9 use different thiazolethione compounds and nitrogen-containing heterocyclic compounds to achieve technical effects comparable to those of Examples 1-4.

[0122] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0123] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. Application of thiazolethione compounds in chemical copper plating, wherein the thiazolethione compounds and nitrogen-containing heterocyclic compounds are used in combination; The thiazolethione compound has a structure shown in Formula I: Formula I; in, R1 is selected from the following free group: hydrogen, C1-C10 carboxyl, substituted or unsubstituted amine, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted silicon and -CO-R4; R4 is selected from C1-C5 alkoxy or C1-C5 alkyl; R2 is selected from the following free group: hydrogen, C1-C10 carboxyl and C1-C10 alkyl; R3 is selected from the following free group: hydrogen, =O and =CH-R5; R5 is selected from H or C1-C5 alkoxy; When R1 is selected from substituted amine, substituted C1-C10 alkyl or substituted C2-C10 alkenyl, the substituents are each independently selected from C2-C5 alkanoyl or C1-C5 alkoxy; when R1 is selected from substituted silicon, the substituent is C1-C5 alkyl.

2. The use according to claim 1, characterized in that The nitrogen-containing heterocyclic compound includes at least one of benzotriazole, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole and mercaptobenzotriazole.

3. The use according to claim 1, characterized in that When R1 is selected from substituted amine groups, the substituent is a C2-C5 alkanoyl group; When R1 is selected from substituted C2-C10 alkenyl, the substituent is C1-C5 alkoxy.

4. The use according to any one of claims 1 to 3, characterized in that: R1 is selected from the following free group: hydrogen, C1-C2 carboxyl, substituted or unsubstituted amine, C1-C4 alkyl, substituted or unsubstituted C2-C3 alkenyl, substituted or unsubstituted silicon and -CO-R4; R4 is selected from C1-C2 alkoxy or C1-C2 alkyl; R2 is selected from the following free group: hydrogen, C1-C2 carboxyl and C1-C4 alkyl; R3 is selected from the following free group: hydrogen, =0 and =CH-R5; R5 is selected from C1-C2 alkoxy.

5. The use according to any one of claims 1 to 3, characterized in that: The thiazolethione compound includes at least one of the following: thiazolidine-2-thione, 3-methylthiazolidine-2-thione, 2-mercapto-4-methyl-2-thiazoline, 3-isopropylthiazolidine-2-thione, 3-isobutyl-2-thiazolidinethione, 3-butyl-2-thiazolidinethione, 1-(2-thioxo-3-thiazoline)ethanone, 2-mercapto-5-thiazolidinone, 2-thioxothiazolidine-4-carboxylic acid, 1-(2-thione-3-thiazolidinyl)-1-propanone, 3-(trimethylsilyl)-2-thiazolidinethione and 2-thione-3-thiazolidinecarboxylic acid ethyl ester.

6. The use according to any one of claims 1 to 3, characterized in that: The mass ratio of the thiazolethione compound to the nitrogen-containing heterocyclic compound is 1:(0.2-5).

7. A chemical copper plating solution, characterized in that The additive comprises an additive; the additive is a combination of a thiazolethione compound and a nitrogen-containing heterocyclic compound; The thiazolethione compound has a structure shown in Formula I: Formula I; Wherein, R1 is selected from the following free group: hydrogen, C1-C10 carboxyl, substituted or unsubstituted amine, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted silicon and -CO-R4; R4 is selected from C1-C5 alkoxy or C1-C5 alkyl; R2 is selected from the following free group: hydrogen, C1-C10 carboxyl and C1-C10 alkyl; R3 is selected from the following free group: hydrogen, =O and =CH-R5; R5 is selected from H or C1-C5 alkoxy; When R1 is selected from substituted amine, substituted C1-C10 alkyl or substituted C2-C10 alkenyl, the substituents are each independently selected from C2-C5 alkanoyl or C1-C5 alkoxy; when R1 is selected from substituted silicon, the substituent is C1-C5 alkyl.

8. The chemical copper plating solution according to claim 7, characterized in that The chemical copper plating solution also includes a copper ion source, a complexing agent, a reducing agent, a pH regulator, a stabilizer and a solvent.

9. The chemical copper plating solution according to claim 8, characterized in that The copper ion source includes at least one of copper sulfate, copper chloride, copper nitrate, copper hydroxide and copper acetate; and / or the complexing agent comprises at least one of potassium sodium tartrate, sodium tartrate, dipotassium tartrate, ethylenediaminetetraacetic acid, disodium ethylenediaminetetraacetate, N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine, sodium salicylate, citrate, triethanolamine, iminodiacetic acid, nitrilotriacetic acid, D-mannitol, xylitol and D-sorbitol; and / or the reducing agent comprises at least one of formaldehyde, hypophosphite, glyoxylic acid, dimethylaminoborane, borohydride salts, ascorbic acid, iron or cobalt complexes, sodium hydroxymethanesulfinate and thiourea dioxide; and / or the pH adjuster includes at least one of sodium hydroxide, potassium hydroxide, sodium carbonate, ammonia water, nitric acid, sulfuric acid, and hydrochloric acid; and / or the stabilizer comprises at least one of 2,2'-bipyridine, 4,4'-bipyridine, phenanthroline and derivatives, thiols, thiothreitol, thioethers, 2,2-thiodiethanol, thiourea and derivatives, cyanide, NaCN, KCN, nickel potassium cyanide, ferrocyanide, K4[Fe(CN)6], thiocyanate, selenocyanate, iodide, sulfite, thiosulfate, polyethylene glycol and polypropylene glycol; And / or in the chemical copper plating solution, the concentration of the additive is 0.1 mg / L-60.0 mg / L, the concentration of the copper ion source is 0.3 g / L-30.0 g / L, the concentration of the complexing agent is 10 g / L-170 g / L, the concentration of the reducing agent is 0.5 g / L to 80.0 g / L, and the concentration of the stabilizer is 0.1 mg / L-50.0 mg / L; And / or the pH of the chemical copper plating solution is ≥8.

5.

10. A chemical copper plating method, comprising using the chemical copper plating solution according to any one of claims 7 to 9 to perform chemical copper plating on a copper-plated part.

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